Page 102 - June 2021

EQUINE HEALTH
Coronavirus has been in the news for more than a year. The new human strain that came from China created
worldwide disease and panic. There are several strains of coronavirus that can affect humans, causing respiratory disease. These include SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome).
Other members of the coronavirus family cause disease in pigs—such as TGE (trans- missible gastroenteritis) and PED (porcine epidemic diarrhea). FIP (feline infectious peritonitis) occurs in cats. Though the human coronavirus is related to the viruses that infect cattle and horses, humans can’t get this disease from cattle or horses.
Coronaviruses are members of the Coronaviridae family, some of which cause
intestinal and respiratory illness in chickens, dogs, cats, pigs, camels, and cattle. Equine Coronavirus (ECoV) belongs to the subfam- ily called Betacoronavirus, a close relative to bovine coronavirus (BCV).
Dr. Geof Smith, College of Veterinary Medicine, North Carolina State University, explains that the coronaviruses are a very diverse family of RNA viruses. These are
a type of virus in which the genetic infor- mation is stored in the form of RNA (as opposed to DNA). The coronaviruses are all characterized by spikes that project outward from their surface. The strains that cause respiratory disease in people and the strains that infect cattle and horses are all different. The bovine coronavirus is in group 2a and all the human respiratory coronaviruses have all been in subgroup 2b, Smith says.
Most cattlemen are familiar with coro- navirus because bovine coronavirus has been
a problem in beef and dairy herds for many years, especially in young calves. Smith says there are three different, but distinct, disease syndromes caused by coronavirus in cattle. Most well-known is diarrhea in young calves. Less common is winter dysentery (a highly contagious gastrointestinal disease) causing diarrhea in adult cattle. Thirdly, bovine coro- navirus is also associated with mild respiratory disease in cattle.
In horses, equine coronavirus has been uncommon and was first thought to only occur in foals, but incidence seems to be increasing in recent years. One of the first outbreaks occurred in 2009, as a mysterious illness in draft horses at a racetrack in rural Japan. In this sport, draft horses compete by pulling a weighted sledge over a 200-meter uphill course (about 219 yards) to see which ones can pull a certain weight the fastest over that distance.
About 600 Ban’ei horses (usually Percheron or a blend of Percheron, Belgian and other heavy breeds that compete in this sport) were housed at that track, and several of them became ill. During the next few months more of the horses were affected, with signs
of fever and sometimes diarrhea. Eventually, 132 of the 600 horses at that track got sick, but all of them recovered within a few days. Japanese researchers who investigated the
EQUINE CORONAVIRUS
by Heather Smith Thomas
One of the first
outbreaks occurred
in 2009, as a mysterious illness in draft horses at a racetrack in rural Japan.
“Though the human coronavirus is related to the viruses that infect cattle and horses, humans can’t get this disease from cattle or horses.”
Coronaviruses are members of the Coronaviridae family, some of which cause intestinal and respiratory illness in chickens, dogs, cats, pigs, camels, and cattle.
100 SPEEDHORSE June 2021